1,211 research outputs found

    Observation of a temperature dependent electrical resistance minimum above the magnetic ordering temperature in Gd2_2PdSi3_3

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    Results on electrical resistivity, magnetoresistance, magnetic Results on electrical resistivity, magnetoresistance, magnetic susceptibility, heat capacity and Gd Mossbauer measurements on a Gd-based intermetallic compound, Gd2_{2}PdSi3_{3} are reported. A finding of interest is that the resistivity unexpectedly shows a well-defined minimum at about 45 K, well above the long range magnetic ordering temperature (21 K), a feature which gets suppressed by the application of a magnetic field. This observation in a Gd alloy presents an interesting scenario. On the basis of our results, we propose electron localization induced by s-f (or d-f) exchange interaction prior to long range magnetic order as a mechanism for the electrical resistance minimum.Comment: 4 pages, 4 figure

    Internet-based framework to support integration of the customer in the design of customizable products

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    Integration of customers is a necessary element to design and produce customer centric products. Design tools and methodologies need to be altered to accommodate customers into the process of designing customized products. In the current paper a mass customization framework is presented, that uses computer-aided design (CAD) and finiteelement-based optimization tools to integrate the customer into the design process via the internet. A mass customization template for generating optimized user-customized products is also presented. The capability of the system is demonstrated by a case study on customization of bicycle frames.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

    Annie Marion Maclean, Feminist Pragmatist and Methodologist

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    Annie Marion Maclean was a major Chicago sociologist and methodologist. She was profoundly influenced by the gendered division of labor in sociology during her era. Maclean combined her work with the men and women of the early Chicago school of sociology and the women of Hull-House, an early social settlement. As a feminist pragmatist, Maclean was both a theorist and practitioner who used qualitative and quantitative methods. She set precedents in the Chicago school of ethnography, participant observation, and critical methodology. Maclean, however, was not the “mother” of ethnography. Harriet Martineau holds a far stronger claim to be a founding contributor to the origin and development of ethnographic methodologies in the social sciences

    Density of Phonon States in Superconducting FeSe as a Function of Temperature and Pressure

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    The temperature and pressure dependence of the partial density of phonon states of iron atoms in superconducting Fe1.01Se was studied by 57Fe nuclear inelastic scattering (NIS). The high energy resolution allows for a detailed observation of spectral properties. A sharpening of the optical phonon modes and shift of all spectral features towards higher energies by ~4% with decreasing temperature from 296 K to 10 K was found. However, no detectable change at the tetragonal - orthorhombic phase transition around 100 K was observed. Application of a pressure of 6.7 GPa, connected with an increase of the superconducting temperature from 8 K to 34 K, results in an increase of the optical phonon mode energies at 296 K by ~12%, and an even more pronounced increase for the lowest-lying transversal acoustic mode. Despite these strong pressure-induced modifications of the phonon-DOS we conclude that the pronounced increase of Tc in Fe1.01Se with pressure cannot be described in the framework of classical electron-phonon coupling. This result suggests the importance of spin fluctuations to the observed superconductivity

    Palaeomagnetic time and space constraints of the Early Cretaceous Rhenodanubian Flysch zone (Eastern Alps)

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    © The Authors 2017. The Rhenodanubian Flysch zone (RDF) is a Lower Cretaceous-lower Palaeocene turbidite succession extending for ~500 km from the Danube at Vienna to the Rhine Valley (Eastern Alps). It consists of calcareous and siliciclastic turbidite systems deposited in a trench abyssal plain. The age of deposition has been estimated through micropalaeontologic dating. However, palaeomagnetic studies constraining the age and the palaeolatitude of deposition of the RDF are still missing. Here, we present palaeomagnetic data from the Early Cretaceous Tristel and Rehbreingraben Formations of the RDF from two localities in the Bavarian Alps (Rehbrein Creek and Lainbach Valley, southern Germany), and from the stratigraphic equivalent of the Falknis Nappe (Liechtenstein). The quality of the palaeomagnetic signal has been assessed by either fold test (FT) or reversal test (RT). Sediments from the Falknis Nappe are characterized by a pervasive syntectonic magnetic overprint as tested by negative FT, and are thus excluded from the study. The sediments of the Rehbreingraben Formation at Rehbrein Creek, with positive RT, straddle magnetic polarity Chron M0r and the younger M'-1r' reverse event, with an age of ~127-123 Ma (late Barremian-early Aptian). At Lainbach Valley, no polarity reversals have been observed, but a positive FT gives confidence on the reliability of the data. The primary palaeomagnetic directions, after correction for inclination shallowing, allow to precisely constrain the depositional palaeolatitude of the Tristel and Rehbreingraben Formations around ~28°N. In a palaeogeographic reconstruction of the Alpine Tethys at the Barremian/Aptian boundary, the RDF is located on the western margin of the Briançonnais terrain, which was separated from the European continent by the narrow Valais Ocean

    Localized inhibition of protein phosphatase 1 by NUAK1 promotes spliceosome activity and reveals a MYC-sensitive feedback control of transcription.

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    Deregulated expression of MYC induces a dependence on the NUAK1 kinase, but the molecular mechanisms underlying this dependence have not been fully clarified. Here, we show that NUAK1 is a predominantly nuclear protein that associates with a network of nuclear protein phosphatase 1 (PP1) interactors and that PNUTS, a nuclear regulatory subunit of PP1, is phosphorylated by NUAK1. Both NUAK1 and PNUTS associate with the splicing machinery. Inhibition of NUAK1 abolishes chromatin association of PNUTS, reduces spliceosome activity, and suppresses nascent RNA synthesis. Activation of MYC does not bypass the requirement for NUAK1 for spliceosome activity but significantly attenuates transcription inhibition. Consequently, NUAK1 inhibition in MYC-transformed cells induces global accumulation of RNAPII both at the pause site and at the first exon-intron boundary but does not increase mRNA synthesis. We suggest that NUAK1 inhibition in the presence of deregulated MYC traps non-productive RNAPII because of the absence of correctly assembled spliceosomes

    Computer, manager, organisatie, deel I en II

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    Magnetic behaviour of Eu_2CuSi_3: Large negative magnetoresistance above Curie temperature

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    We report here the results of magnetic susceptibility, electrical-resistivity, magnetoresistance (MR), heat-capacity and ^{151}Eu Mossbauer effect measurements on the compound, Eu_2CuSi_3, crystallizing in an AlB_2-derived hexagonal structure. The results establish that Eu ions are divalent, undergoing long-range ferromagnetic-ordering below (T_C=) 37 K. An interesting observation is that the sign of MR is negative even at temperatures close to 3T_C, with increasing magnitude with decreasing temperature exhibiting a peak at T_C. This observation, being made for a Cu containing magnetic rare-earth compound for the first time, is of relevance to the field of collosal magnetoresistance.Comment: To appear in PRB, RevTex, 4 pages text + 6 psFigs. Related to our earlier work on Gd systems (see cond-mat/9811382, cond-mat/9811387, cond-mat/9812069, cond-mat/9812365

    Rye (Secale cereale L.) for biogas production – Breeding capability

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    In den vorliegenden Untersuchungen wurde divergentes Roggenmaterial (Populationssorten mit Körner- und Grünschnittnutzung, Hybriden, aktuelles Zuchtmaterial, Tetraploider Roggen, pflanzengenetische Ressourcen (PGR)) in einem zweijährigen Anbau anhand seiner Biomasseleistung auf seine Eignung zur energetischen Nutzung von Roggen überprüft, die erfassten agronomischen Merkmale wurden auf ihre Relevanz für die Biomasse­bildung beurteilt, verschiedene Schnittzeitpunkte zur Biomassenutzung untersucht und über einen NIRS-Ansatz Aussagen über das Gasbildungsvermögen der untersuchten Roggenformen getroffen. Für die Merkmale Gesamttrockenmasseertrag (GTM-Ertrag) und Biogasausbeute zu zwei Grünschnitt-Zeitpunkten – Mitte Ährenschieben und Milchreife – sowie Kornertrag lagen im untersuchten Material signifikante genotypische Varianzen vor. Bei den Grünschnitten 1 und 2 betrugen die mittleren GTM-Erträge 70,1 und 131,9 dt/ha. Grünschnittroggen-Sorten erwiesen sich im 1. Grünschnitt und Hybriden im 2. Grünschnitt als über­legen, wogegen in der Testkreuzungsleistung beim 2. Grünschnitt mehrere Grünschnittroggen und PGRs sowie eine Populationssorte die höchsten GTM-Erträge zeigten. Bei den Grünschnitten 1 und 2 sowie dem Kornertrag ergaben sich beachtliche Heterosiszuwächse von durchschnittlich 9,3%, 11,6% bzw. 32,3%. Bedeutsame Merkmale für die Biomasseproduktion (Wuchshöhe, Termin Ährenschieben, TS-Gehalt) wurden identifiziert und deren Korrelationen berechnet. Die für das Gasbildungsvermögen wesentlichen Inhaltstoffe konnten mittels NIRS-Untersuchungen quantifiziert und die Biogas­ausbeute rechnerisch bestimmt werden. Korrelationen zwischen dem GTM-Ertrag, der Biogasausbeute und dem Ligningehalt wurden ermittelt. Die Ergebnisse unter­streichen das hohe Biomassepotenzial verschiedener Roggen-Materialgruppen für die Bioenergienutzung.The focal points of the present investigation were to examine the suitability of different rye forms (population varieties with forage grain use, hybrids, current breeding material, tetraploid rye, plant genetic resources) for biomass production, to identify the ideal growing stage for harvesting the biomass of these rye forms, to identify relevant traits for biomass production and to estimate their potential of gas production by NIRS analysis. In a two-year trial, significant genetic variances in both the population per se (pps) performance and the testcross performance were demonstrated for total dry matter (TDM) yield at cutting dates 1 and 2 as well as for grain yield. At cutting dates 1 and 2 the average yields amounted to 70.1 and 131.9 dt/ha TDM, respectively. Forage rye materials were superior with regard to TDM yield at cutting date 1 while forage rye, plant genetic resources and a population variety achieved the highest TDM yield at cutting date 2 in the testcross performance. The heterotic increase averaged a substantial level of 9.3%, 11.6% and 32.3% at cutting dates 1 and 2 and for grain yield, respectively. Traits with high relevance for biomass production were identified (height, date of ear emergence, dry mass content) and correlations were calculated. The biogas production of the rye entries was assessed by quantifying the essential ingredients for biogas production via NIRS. Correlations between the TDM yield, the biogas production and the content of lignin were determined. The high capability of different rye forms for bioenergy recovery was underlined
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